In this study was investigate the effect of vegetative treatment with the herbicides Basagran 480 SL, Pulsar 40 and Express 50 WG on the fat content of seeds of different Bulgarian cotton cultivars. The experiment was carried out with twelve Bulgarian cotton cultivars (Gossypium hirsutum L.) - Chirpan-539, Helius, Trakia, Vicky, Philipopolis, IPK-Veno, Boyana, Avangard, Natalia, Darmy, Dorina and Nelina. The herbicides were applied at the bud formation stage of cotton. Fat content in cotton seeds was determined by extraction - SR ISO 6492 method. For the first time in the world it has been established that in the vegetative treatment with herbicides the most valuable with regard to cotton seed fat content are all cultivars treated with Basagran 480 SL, except Chirpan-539 and Helius. It has been established that the treatment with the Express 50 WG herbicide less affected the cultivars Chirpan-539, Helius, Trakia, Vicky, Philipopolis, IPK-Veno, Boyana, Avangard, Natalia but all cultivars were negative influenced by the treatment with the herbicide Pulsar 40 with regard to fat content in seeds.

The present research paper aims at comparing the similarity and remoteness of influence of the features of eight common wheat varieties and their grouping on the base of important structural indicators through the use of a mathematical approach and a cluster analysis; studying of a relationships between the examined indicators in order to make more objective evaluation using the possibilities of the factor analysis; reducing the number of correlating indicators into new factors. Two-year data were used, obtained from the examination of eight common wheat varieties. The subject of the present research were seven seven foreign varieties of wheat - Ingenio, Bologna, Dalara, Moyson, Falado, Gabrio, Pibrak, and the eighth variety - Factor - was a local Bulgarian selection. The introduction of common wheat varieties is related to the study of their productivity and ecological plasticity. For this purpose there were reported and analised yield structural elements: plant height, wheat-ear length, number of ears, number of grains per ear, weight of grains per ear, grain yield from hectare. The cluster analysis showed that the influence of wheat variety on the qualitative indicators led to their grouping into two new clusters. There was established a strong positive correlation between the number of grains per ear and the hectoliter mass (r = 0.811) as well as between the number of ears and the weight of grains per ear (r = 0.771). The correlation coefficient between the number and weight of grains - (r = 0.649). The factor analysis established the influence of three main factors influencing the group formation of wheat varieties. The first factor was related basically to plant height, ear length, number of grains per ear and hectoliter mass. The second component was basically related to the number of ears and weight of grains. The third factor was related to the mass of 1000 grains.

The aim of the study was to determine the various ways of fertilization of wheat, in accordance with characteristics of the chosen varieties, pre-plant and the pedo-climatic conditions specific to the Burnas Plain. Through the research, the quantitative and qualitative increase of the wheat production, the differentiation according to the biological material used (variety) was pursued, all based on the use of 5 variants of fertilization, emphasizing also the costs involved by each of them-parallel input-output for the economic efficiency of culture. The results obtained from the experiments carried out during this period offer, as a novelty element, multi-level comparisons between the Romanian wheat varieties and the Austrian premium varieties provided by SC Probstdorfer Saatzucht Romania SRL [1]. The researches took place in the Burnasului Plain, within the S.C.D.A. Teleorman (Drăgăneşti-Vlaşca), on soils of the molisoluri type, cernoziom cambic type, with medium, clay-claytexture..The research that led to the production of production results is extremely different, depending on the environmental conditions (among which the climatic ones had the greates timpact) on the influence of the fertilizers and the wheat varieties used in the study. Production results show that any of the fertilization variants yields significant wheat yields. With the exception of the Biovin 150kg treatment only, when production increases by 15.48-23.31% compared to the untreated control (maximum 896 kg / ha in 2014-2015), all other fattening systems (N80, P80 and complex-N80 + P80 + Biovin 150) are statistically assured in the favorable years (2014-2015, 2015-2016.) with increases of 40-75%-2373.33 kg / ha at N80, 2863.33 kg / ha at P80 and 2869.33 kg / ha at the complex in .2014-2015. The data showed that, as a whole, Romanian varieties .are better responding to this differentiated fattening (N80, P80, Biovin 150) compared to premium varieties. Regarding the application of the NPB (N80 + P80. + Biovin 150) complex, both Romanian and premium varieties offer similar production incrases.

For the first time in the world we established that the highest protein content in seeds of cultivar Helius was obtained with vegetative treatment with herbicides Goal 2 E, Linuron 45 SC, Wing P and Merlin 750 WG. The highest protein content in seeds of cultivar Darmy was obtained with vegetative treatment with herbicides Goal 2 E, Wing P and Basagran 480 SL. The highest phytotoxicity on protein content in seeds of cultivar Helius was shown by the herbicide Basagran 480 SL and all herbicide combinations with the growth regulator Amalgerol and the foliar fertilizer Lactofol O. The strongest phytotoxic effects on seeds of cultivar Darmy was produced by the herbicides Linuron 45 SC and Merlin 750 WG and herbicide mixture Wing P + Lactofol O. For the first time, we established that, from the point of view of the technology for cotton growing of cultivar Helius, the most valuable are tank mixtures Goal 2 E + Amalgerol, Linuron 45 SC + Amalgerol, Goal 2 E + Lactofol O, as well as the single use of herbicides Goal 2 E, Linuron 45 SC, Wing P and Merlin 750 WG. Technologically the most valuable in cotton cultivar Darmy were herbicide combinations Goal 2 E + Amalgerol, Wing P + Amalgerol, Merlin 750 WG + Amalgerol, Basagran 480 SL + Amalgerol, Goal 2 E + Lactofol O, Linuron 45 SC + Lactofol O, Merlin 750 WG + Lactofol O and Basagrain 480 SL + Lactofol O, and the herbicides Goal 2 E, Wing P and Basagran 480 SL.

The action of some foliar herbicides and herbicide combinations for control of common wheat (Triticum aestivum L.) weeds was studied. To that end against the background of soil applied Stomp 330EK New at a dose of 5 l/ha the herbicides Axial 050EK, Granstar 75DF, Derby Super WG, Sekator OD, Lintur 70WG, and the tank mixtures of Axial with the other herbicides applied in the tillering phenophase of the crop were studied. The species composition and density of weeds was assessed using the quantitative method prior to treatment and after herbicide treatment on days 5, 15 and 30, by constant metering. The herbicide Lintur 70WG and its combination with Axial 050EK had the fastest initial effect. The highest herbicidal effect (99.5%) against annual monocotyledon and dicotyledon weeds showed the combination of Derby Super WG 33 g/ha + Axial 050EK - 900 ml/ha. Very good was the effect of the other herbicidal mixtures between anti-broadleaf herbicides and the graminaceous herbicide Axial 050. All applied herbicides and herbicide mixtures showed a very good after-action on weeds.